This disclosure relates to solder resistant high temperature compositions and methods for manufacturing the same.
Because of the desire to miniaturize products and to improve productivity in the electronics industry, a method of soldering resinous electronic parts has been developed for affixing parts such as connectors, switches, relays and coil bobbins to printed circuit board. This method has been named a “surface-mount” technology.
The term “surface-mount” as used herein refers to a mounting system wherein electronic parts are affixed to a printed circuit board. A creamy lead-free solder is used to facilitate the adhesion of the electronic parts to the printed circuit board. Thermoplastic compositions are also often used as insulating materials for electronic parts. The printed circuit board is then passed through a heating oven (re-flowing oven), thereby melting the solder to fix the electronic parts to the wiring board. The surface-mount technology permits mounting to be conducted on both surfaces of the printed circuit board thereby reducing production costs.
However, the surface-mount technology suffers from several drawbacks. For example, upon exposure to a lead-free solder, many of the thermoplastic compositions that are used as insulators begin to fail. Loss of insulating ability, which generally occurs after failure, renders the thermoplastic composition unreliable for these types of applications. It is therefore desirable to have thermoplastic compositions that can contact lead free solder without any of the aforementioned disadvantages.